Some industrial, commercial, aerospace and military systems depend on reliable pressure sensors for fluid (including gas) handling. Pressure sensors are used to measure fluidic pressure in a variety of different areas of discipline. Among recent trends is the increasing use of meso technology. Meso technology uses relatively small devices and an electrostatic force to move diaphragms within the pressure sensors. The electrostatic force is often applied by applying a voltage between two paired electrodes, which are commonly attached to a selected wall and/or a diaphragm. The electrostatic force results in an attractive force between the paired electrodes, which moves the selected wall or diaphragm toward one another.
When pressure sensors are manufactured, they may be trimmed or calibrated in the factory. There is an associated cost with trimming each pressure sensor that, in some cases, may exceed the cost of manufacturing the pressure sensor. However, without first trimming the pressure sensor, the pressure sensor may be inaccurate at a current set of conditions.
Regardless of accurate factory trimming, a diaphragm of the pressure sensor may also be compromised by mechanical stress, aging, and a number of environmental factors such as temperature, humidity, and atmospheric pressure. As a result, the accuracy of the pressure sensor may be compromised in the “field.”
In the figures, like reference characters designate identical or corresponding components and units throughout the several views.